Anthropic says Claude identified how the unexplained seed values behind major NIST elliptic-curve cryptography standards were generated. In under half an hour in October 2026, an internal research model determined that seeds for NIST P-192, P-224, P-256, P-384 and P-521 were outputs of the legacy C-library lrand48 pseudorandom-number generator initialized with Unix timestamps, rather than hashes of secret phrases or other cryptographic algorithms. NIST adopted these curves in 2000 for the FIPS 186-2 Digital Signature Standard, while the NSA had supplied their seed values without explaining their provenance. Anthropic reconstructed timestamps from May 1997 through April 1998 and the candidate positions that reproduce ten prime-curve and binary-curve seeds; P-256, for example, was the 1,842nd 20-byte candidate from its run. Anthropic says the result is not a cryptographic break or a newly discovered weakness, and that the simple reproducible process makes intentional backdoors less plausible. Claude also traced base points for P-192 and five ANSI X9.62 example curves to the FreeLIP random-number generator, but could not explain base points for P-224, P-256, P-384, P-521 or NIST binary curves. B-163 remains unexplained. Anthropic will donate the $36,864 NIST elliptic-curve seeds bounty to the Internet Security Research Group.

AI advice decreased the ability to suspend judgment from 44% to 3% and lowered accuracy from 27% to 9%, while confidence increased from 30% to 76%. The willingness to say "I don't know" dropped significantly when AI was available, and monetary incentives had minimal impact.